An alternative synthetic access to cis-4a-Methyloctahydrophenanthrene, a biomarker of Sergipe-Alagoas Basin petroleum in Brazil

cis-4a-Methyloctahydrophenanthrene (1) was prepared in 8 steps (23% overall yield) from 2-bromophenyl)acetic acid (3) and cyclohexane-1,3-dione (6). A highly cis-diastereoselective Michael-type Heck coupling served as the key step in the assembly of the tricyclic skeleton. This compound 1 was used as gas chromatography standard which allowed the unequivocal identification of a minor biomarker present in Carmopolis oil from the Sergipe-Alagoas Basin in Brazil.13566466

Binding Events of (S)-N-(3-Oxo-octanoyl)-homoserine Lactone with Agrobacterium tumefaciens Mutant Cells Studied by Saturation Transfer Difference NMR

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Quorum-sensing is a widely studied communication phenomenon in bacteria, which involves the production and detection of signaling substances in relation with cell density and colony behavior. Herein, the membrane binding interactions of the signal (S)-N-(3-oxo-octanoyl)-HSL with A. tumefaciens NTL4(pZLR4) cells were studied using saturation transfer difference NMR spectroscopy (STD-NMR). The substance epitope map was obtained showing that the hydrophobic acyl chain is the most important interacting site for the signal and the cell membrane. Results were interpreted upon comparisons with a simpler system, using liposomes as membrane models. Some insights on the use of beta-cyclodextrin as acyl-HSL carrier were also provided.224702708Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)FAPESP [05/02934-4, 07/52389-8]CAPES [141841/2006-0

Exopolymeric Substances (EPS) Produced by Petroleum Microbial Consortia

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Microbial consortia recuperated of crude oil samples from the Pampo Sul field, Campos Basin, RJ, produced biosurfactants in mineral media containing glucose and 9,10-dihydrophenantrene, n-nonadecane, nonadecanoic acid, slightly biodegraded crude oil (P1) or heavily biodegraded crude oil (P2) as carbon sources. The production of exopolimeric substances (EPS) and petroleum biodegradation do not necessarily occur simultaneously. The EPS analyses by infrared and eletronspray ionization mass spectrometry (ESI-MS) revealed a mixture of surfactine isoforms. The biosurfactants reduced the surface tension of water and Zinder medium from 72.4 and 55.7 to 28.6 mN m(-1). Additionally, this surfactant emulsified different oils in water with performances similar to or better than of a conventional surfactant, Tween 80.21815171523FINEPPETROBRASCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

TRITERPENES OF SCHINUS-TEREBENTHEFOLIUS

13365966

SYNTHESIS AND C-13 NMR-STUDY OF SOME PODOCARPIC ACID-DERIVATIVES

1032432

Absolute configuration and antimicrobial activity of acylhomoserine lactones

(S)-N-Heptanoylhomoserine lactone is an uncommon acyl odd-chain natural product employed by many Gram-negative bacteria as a signaling substance in chemical communication mechanisms known as quorum sensing. The absolute configuration determination of the metabolite produced by the phytopathogen Pantoea ananatis Serrano is reported herein. As with all other substances of this class, the lactone moiety possesses S configuration, corroborating the hypothesis that it shares the same biosynthetic pathway as the (S)-N-hexanoylhomoserine lactone and also that some LuxI homologues can accept both hexanoyl- and heptanoyl-ACP as precursors. Evaluation of the antimicrobial activity of enantiomeric acylhomoserine lactones against three Gram-positive bacteria (Bacillus cereus, B. subtilis, and Staphylococcus aureus) revealed important features between absolute configuration and antimicrobial activity. The N-heptanoylhomoserine lactone was considerably less active than the 3-oxo derivatives. Surprisingly, non-natural (R)-N-(3-oxo-octanoyl)homoserine lactone was as active as the S enantiomer against B. cereus, while the synthetic racemic product was less active than either enantiomer.7161032103

Microbial monooxygenases applied to fragrance compounds

Biotransformation is an important tool in organic syntheses, especially for the production of chiral molecules and whenever chemical reactions are inefficient. Fragrance compounds were biotransformed by Trichosporum cutaneum CCT 1903 whole cells. Batch reactions with cis-jasmone (1), (R)-(-)-carvone (3), alpha- and beta-ionones (4, 5) and (R)-(+)-limonene (10) produced 4-hydroxyjasmone (1a), 7,8-epoxyjasmone (1b), 7,8-dihydroxyjasmone (1c), (1S,2R,4R)-neoisodihydrocarveol (3a), (6R)-isoprenyl-(3R)-methyl-2-oxo-oxepanone (3b), (3R)-isopropenyl-6-oxoheptanoic acid (3c), 2,3-epoxy-(5R)-isopropenyl-2-methylcyclohexenoI (3d), alpha-homo-cycloaeraniol (4a), 4-oxo-7,8-dihydro-beta-ionone (5a), uroterpenol (10a) and (R)-(+)-limonene-1,2-diol (10b) as pure samples for spectroscopic identification (H-1 and C-13 NMR,H-1,H-1-gCOSY, HSQC, gHMBC). The stereochemical consequences of the transformations are also discussed. (c) 2006 Elsevier B.V. All rights reserved.442788

Total structural assignment and absolute configuration of terreinol by C-13 and H-1 NMR

The carbon-carbon connectivity of terreinol, a new metabolite isolated from Aspergillus terreus, and its previous C-13 assignments were confirmed by a two-dimensional INADEQUATE experiment using a few milligrams of the compound with natural C-13 abundance. The carbon-carbon correlations were determined by computational analysis (with >99% probability) of this experiment. Additionally, the absolute configuration of terreinol was achieved indirectly via its corresponding secondary alcohol by the modified Mosher method allied to conformational analysis. The shielding effect of the phenyl group of methoxytrifluoromethylphenylacetic acid (MTPA) on the substituents of the carbonylic centre gave a fully regular Deltadelta(SR) sign distribution, allowing reliable assignment of the R configuration for terreinol. Copyright (C) 2004 John Wiley Sons, Ltd.43325125

Mechanistic investigation of the Candida albicans CCT 0776 stereoinversion system and application to obtain enantiopure secondary alcohols

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Phenylethanol deracemization with Candida albicans CCT 0776 whole cells yields the (R)-enantiomer in over 99% enantiomeric excess and 98% yield. The deracemization process involves, in the first step, a fast, highly (S)-selective oxidation (NADP and O(2) dependent) and, in the second step, a slower partially (S)selective reduction (NADH dependent) of the intermediate ketone. The process was extended to other 2-alkanols, 1,2-diols and 1,3-diols and, with the exception of 1,3-diol (unreactive), the enantiomeric excess and yield of the deracemization were about 99% and 62-98%, respectively. (C) 2009 Elsevier Ltd. All rights reserved.202226352638PETRO-BRASConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES